Refrigerating apparatus



PR 22, J, A. CONRADY REFRIGERATING APPARATUS Filed March 10, 1937 INVENTOR. Jon/v me/wx ATTORNBYB.

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denser and receiver -vessel separate from the evaporator.

. syphon Vbetween will be transferred I atented Apr-.22, -1941 lUNITED ySTATES PATENT OFI-lcs .assalto n'js i corporation of Ohio John A. Com-adr, Cincinnati. Ohio, assignor to-v The Crosley Corporation,

Cincinnati. Ohio, a l

' i Applicaties March 1o, 1931, serial No. indias My invention' relates specifically tothe receiver evaporator in refrigerating apparatus of the intermittent absorption type.

In refrigerating apparatus operative on the intermittent absorption principle. a refrigerant such as ammonia is employed and an absorbent such as water. The strong liquor or concentrated solution of ammonia inthe water-is boiled in a vessel commonlycalled a generator. This same vessel usually functionsa as an absorber. Heat is applied during the heating cycle to cause the boiling off of the refrigerant. The refrigerant, in gaseous form,

in which the gaseous refriger-v ant is condensed to a liquid and, pending its use during 4,the evaporation cycle.l stored. Toward the end of the heating cycle the liquiiied refrigerant ls transferred from the receiverv to ythe inner -shell of the evaporator in which the expansion of the refrigerant to gaseous condition takes up heat which induces such cooling as-is' required for freezing-ice cubes and generally cooling the cooling chambers of the refrigerator.

lIn some apparatus of the intermittent absorp-v tion type the receiver acts also as the evaporator., but in 'the particular combination with which .I shall describe my inventio the receiver is a It is one object of my invention to employ a the receiver and the evaporator to' cause the liquid refrigerant trapped in the re'- ceiver, to be transferred substantially completely to the evaporator, once the cycle is started.

Another object is the provisionof achamber surrounding the ice cube vcompartment which is filled with a gaseous refrigerant such as sulphur dioxide, said refrigerant causing a blanket of gas between bottom of evaporator and liquid level of refrigerant surrounding ice cube compartment so that during heating cycle a minimum amount of heat will be transferred from warm gas in evaporater to ice. cube compartment, and. which also, during the evaporating cycle will act as a secondary refrigerating system.' thereby cooling and freezing the ice cube compartmen Another object of my inventionis the provi sion of a return tube generator absorber vwhichjis so constructed and arranged and'so supplied from a trap or sump that when condensed refrigerant is received. vit

panded refrigeratlnggas will'also return tothe absorber throuah this same tube.

.c (ci. ca -ns) passes under pressure to a cona compartment surroundingv the ice cube chamber in which an exposed chilled surface of the compartment, cooled bythe expansion oi the `primary refrigerant, in this example liquid am-A monia, will induce a circulation of the secondary refrigerant which will cycles of condensation andexpansion'necessary to refrigeration.

The above objects and other objects towhich reference will be made in the ensuing description, I accomplish by that certain combination and arrangement of parts of which I have illustrated al preferredembodiment. y

Referring to the drawing: Figure l is a diagrammatic sectional view of lthe refrigerating apparatus.

Fig. 2 isa sectional view ofthe evaporatorV taken along the lines 2-2 of Fig. l.

Fig. 3 is a sectional view of the refrigerator similar to that in Fig. 2, excepting that the operation ofthe secondary refrigerating system is diagrammatically illustrated.

The generator absorber is'illustrated at I. vAt one end of the generator absorber, there is a dome 2 containing the usual rectifying apparatus.

Altube I permits the gasiiied ammonia and liquor entrained therewith to pass into the drum 4. From the drum 4., a tube 5 provides an outlet for the expanded gases which pass upwardly through the entrained liquor trapped in the dome; An

' overflow l drains the dome 2 after the entrained liquor has filled up the dome to the level of the top of the tube 1.v The overflow through the tube 1 drains back into the still absorbent.

'Ihe apparatus also acts as a separator forl the gasiiled refrigerant.

From the top of lthe dome 2, a tube 8 passes to .the condenser coil 9 which is shown as arf ranged in atank Il, cooled with some cooling liquid suchas water.'`

.A tube Il is connected to the discharge or out-v let fromthe condenser coil I and this drains the. A

condensed duid into the receiver I2.

from the-evaporator to the e tothe absorber'but that exlishment of a secondary re rig'erating in In the receiver 2 there is a return bent tube l Il through which the condensed refrigerant passes tb the evaporator il.

To prevent the liquor being forced by pressure from the sump -IB intothe'evaporartor iI,-I have' provided a pressure relief' tube Il having an inlet* i1 at the top of the tube. .Pressure is equalized. between the receiver i2 and the evaporator Il by I means of thetube il until the level of condensed refrigerant. indicated in-dotted lines inFlg. 1, has' reached the inlet' I1 to the tube Il. Then whenl the inlet i1 ofthe tube IO is sealed, the

probably pass through the l evaporator.

The evaporator Il has a false bottom I8 having a sump I8 at a low point therein. The small opening permits the condensed liquid to feed either in a very fine string or drop by drop into the evaporating chamber 2| which is formed by the space in the evaporator I4 below the false bottom plate I8. 'I'he bottom of the evaporator I I has a sump 22 from-which a tube 23 permits the expanded gas and unexpanded liquor to pass down through the tube 23 into another dome 2l arranged at the end of the generator opposite the dome 2.

described will not occur. In 'any event, the chilled bottom wall of the evaporator I4 will cause a circulation of the sulphur dioxide gas, the cold gas passing down and striking the top wall of the chamber 21 and the warm gas passing up along the outer walls of the chamber 28.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1.` In refrigeration apparatus of the intermittent absorption type in combination with the evaporator, a shell spaced from the lower wall of said evaporator forming a secondary evapo- A tube drains the expanded gas and unex- A panded liquor which passes down the pipe 23 vback into the generator absorber. Y

During normal operation, there will be some entrainment of unevaporated refrigerant through the pipe 23 into the dome 24, but such unevaporated refrigerant will illl in the dome 24 to the level of the top of the tube 25 and as soon as any additional refrigerant is entrained, it will be returned to the weak liquor in the generator I.

A pressure equalizing tube 28 connects the dome 24 with the dome 2. This prevents the building up of too much pressure on the pressure side of the system.

'Ihe ice-cube chamber, as indicated at 21, is formed by a rectangular shell which is set into the end walls of the compartment 28, the end joints being preferably formed by a welding operation. H

The compartment 28 is' secured to the evaporator Il so that the walls thereof are welded to the evaporator in substantially the position illustrated in Figs. 2 and 3. Consequently the lower half oi' the evaporator I4 is set into the top wall of the compartment 28.

Within the compartment 28 a secondary refrigerating system is set up. A preferred refrigerant is sulphur dioxide. In the illustration in Fig. 2 the system is shown during the generating cycle at which time, the evaporator I4 becomes warm. The lower wall, were it not for the presence of the sulphur dioxide gas acting as an insulator rapidly exchangesits heat to the walls of the cooling compartment 21. As the sulphur dioxide gas -is warmed up, the warm gas rises to the top of the compartment 28 and an atmosphere of cool sulphur dioxide liquid remains in the lower portion of the compartment 28 which prevents heat being transferred from the evaporator.

During thelevaporating cycle illustrated diagrammatically in Fig. 3, the condensed refrigerant, ammonia, drips through the small opening rator: and a drip opening at a low point in said shell to permit the gravity flow of condensed refrigerant from above said shell into said secondary evaporator.

2. In refrigeration apparatus of the intermittent absorption type an evaporator having a shell interposed therein forming a receiver compartment in the portion above the shell and a secondary evaporator below said shell and means including a restricted opening at a low point in said shell for controlling the introduction of liquid refrigerant from said receiver compartment into said secondary evaporator.

3. In refrigeration apparatus of the intermittent absorption-type an evaporator having a shell interposed therein forming a receiver compartment in the portion above the shell and an evaporating chamber below said shell and means for controlling the introduction of liquid refrigerant from said receiver compartment into said evaporating chamber comprising a restricted orifice at a low point in said receiver, said portion below said shell being housed in a gaseous atmosphere within which a freezing chamber is also'housed.

4. In refrigeration apparatus of the intermittent absorption type an evaporator having a shell interposed therein forming a receiver compartment in the portion above the shell and an evaporating chamber below said shell and means for controlling the introduction of liquid refrigerant from'said receiver compartment into said evaporating chamber comprising a restricted oriflce at a low point in said receiver, said portion below said shell being housed in a gaseous atmosphere `within which a freezing chamber is also housed. saiid gaseo atmosphere comprising sulphur diox de.

5. In 'refrigerating apparatus of the intermittent absorption type, an evaporator having a shell interposed therein forming a receiver in the portion above the shell in the portion below the shell, means for introducing a condensed refrigerant from said receiver to said evaporating, chamber, a still absorber and means for returning the refrigerant in both gaseousLand liquid form from said evaporator to said still absorber.y f

6. In rfrigerating apparatus'ofthe intermittent absorption type.' an evaporator having a shell interposed therein forming a receivr in the portion above the shell and an evaporating chamber in the portion below the shell, means for introducing a condensed refrigerant from said receiver to said evaporating chamber, a still absorber and means for returning they refrigerant in both gaseous and liquid vform from said evaporator to said still absorber comprising a tube having an intake in a sump arranged at a low point in said evaporator.`

JOHN A. CONRADY.

and an evaporating chamberl 

